Web (webpage) application is an application program which is wrote by using a language supported by the browser and takes the browser as operating and presenting environments. When a user uses a Web application, in order to ensure the security of usage of network system resources, performing an identity authentication on the user is usually needed, so that a legitimate user accesses network system resources with a legitimate authority.
In the prior art, generally, the identity authentication of a user is performed by using a username and a password input by the user, the user needs to remember the username and the password, moreover, the password is easy to be intercepted by a third party during a transmission process, the security is not high, and inputting the password is relative troublesome and not convenient enough.